تويت
Flash lighting
اضاءة الفلاش _فن التصوير
Henry Fox Talbot first used light from a spark to take experimental photographs of close objects in 1851. And while the " better " pro- . fessional studios struggled with limelight in the 1880s , the less ex pensive studios , and most amateur photographers , were using " magnesium lighting " the forerunner of photographic flash
Magnesium burns with an intense bluish white light . At first a mag nesium ribbon was held in tongs and burnt slowly for a few seconds or minutes . The advantages of this light source were its low cost and portability . Magnesium gives a brighter , much briefer duration light if ground up into powder . Various forms of flash powder were made - most ignition systems used an air ball to blow the powder into a gas flame . Flash duration varied between 1/10 and 10 seconds depending on the amount of powder used . As magnesium burns it gives off a dense white smoke . Some studios used a ceiling hood lined with wet canvas to absorb the smoke and ash . From the 1880s " flashpowder " ( a mixture of ground magnesium and an oxygen - producing chemical ) became available . Large quantities could be burnt in about 1/30 of a second after the appli cation of a spark , and flashguns were made incorporating a flint type gas lighter . By spreading flashpowder in a long shallow tray and igniting it at the center , photographers cou could produce a light ing quality similar to today's soft floodlighting . Flashbulbs date from 1929. They were originally the size of an electric light bulb , and contained crumpled magnesium foil in an atmosphere of oxygen . Low voltage from a battery was used to ignite an internal fuse and the bulb burnt for about 1/25 of a second . For the first time photographers could synchronize flash to fire with the opening of the shutter . This was of special use to newspaper photographers such as Weegee ( see The individualists , pp.355-6 ) , who often had to " snatch " a picture even in the poorest lighting conditions . Smaller and more efficient bulbs ( using zirconium wire ) are used for cubes and bar flashes today .. Practicable electronic flash dates from the 1940s . Since that time , better electronic components have allowed improvements in two directions . Compact hand units have become even smaller and well able to compete in power with flashbulbs . Larger units are powerful enough to provide complete studio requirements . The lack of heat and continuous glare makes photography more com fortable for the sitter or model , and the photographer has the free dom of movement that comes with using the camera without a tripod . The flexibility of different lighting heads and the abundance of power has in recent years encouraged photographers to return to simpler , daylight - quality style , using flash illumination bounced off white studio walls reflectors . YEH
استخدم هنري فوكس تالبوت الضوء المنبعث من شرارة لأول مرة لالتقاط صور تجريبية لأجسام قريبة في عام 1851. بينما كان المؤيد "الأفضل". كافحت الاستوديوهات الاحترافية مع الأضواء في ثمانينيات القرن التاسع عشر ، وكانت الاستوديوهات الأقل اهتمامًا ، ومعظم المصورين الهواة ، يستخدمون "إضاءة المغنيسيوم" التي سبقت فلاش التصوير الفوتوغرافي.
استخدم هنري فوكس تالبوت الضوء المنبعث من شرارة لأول مرة لالتقاط صور تجريبية لأجسام قريبة في عام 1851. بينما كان المؤيد "الأفضل". كافحت الاستوديوهات الاحترافية مع الأضواء في ثمانينيات القرن التاسع عشر ، وكانت الاستوديوهات الأقل اهتمامًا ، ومعظم المصورين الهواة ، يستخدمون "إضاءة المغنيسيوم" التي سبقت فلاش التصوير الفوتوغرافي.
Magnesium flash powder
Magnesium could be ignited in several ways : by blowing it into a candle flame ( above ) . pouring it through a funnel and applying a flame to it as it fell ( left ) . a or placing it on a tray and using a flint and wheel , triggered by a lever on the handle ( below ) , to make a spark . Flash duration was from 1 / 10-10 sec .
مسحوق فلاش المغنيسيوم يمكن إشعال المغنيسيوم بعدة طرق: عن طريق نفخه في لهب الشمعة (أعلاه). صبها من خلال قمع ووضع لهب عليه عند سقوطه (على اليسار). أ أو وضعها على صينية واستخدام صوان وعجلة ، يتم تشغيلهما بواسطة رافعة على المقبض (أدناه) ، لإحداث شرارة. كانت مدة الفلاش من 1 / 10-10 ثانية.
اضاءة الفلاش _فن التصوير
Henry Fox Talbot first used light from a spark to take experimental photographs of close objects in 1851. And while the " better " pro- . fessional studios struggled with limelight in the 1880s , the less ex pensive studios , and most amateur photographers , were using " magnesium lighting " the forerunner of photographic flash
Magnesium burns with an intense bluish white light . At first a mag nesium ribbon was held in tongs and burnt slowly for a few seconds or minutes . The advantages of this light source were its low cost and portability . Magnesium gives a brighter , much briefer duration light if ground up into powder . Various forms of flash powder were made - most ignition systems used an air ball to blow the powder into a gas flame . Flash duration varied between 1/10 and 10 seconds depending on the amount of powder used . As magnesium burns it gives off a dense white smoke . Some studios used a ceiling hood lined with wet canvas to absorb the smoke and ash . From the 1880s " flashpowder " ( a mixture of ground magnesium and an oxygen - producing chemical ) became available . Large quantities could be burnt in about 1/30 of a second after the appli cation of a spark , and flashguns were made incorporating a flint type gas lighter . By spreading flashpowder in a long shallow tray and igniting it at the center , photographers cou could produce a light ing quality similar to today's soft floodlighting . Flashbulbs date from 1929. They were originally the size of an electric light bulb , and contained crumpled magnesium foil in an atmosphere of oxygen . Low voltage from a battery was used to ignite an internal fuse and the bulb burnt for about 1/25 of a second . For the first time photographers could synchronize flash to fire with the opening of the shutter . This was of special use to newspaper photographers such as Weegee ( see The individualists , pp.355-6 ) , who often had to " snatch " a picture even in the poorest lighting conditions . Smaller and more efficient bulbs ( using zirconium wire ) are used for cubes and bar flashes today .. Practicable electronic flash dates from the 1940s . Since that time , better electronic components have allowed improvements in two directions . Compact hand units have become even smaller and well able to compete in power with flashbulbs . Larger units are powerful enough to provide complete studio requirements . The lack of heat and continuous glare makes photography more com fortable for the sitter or model , and the photographer has the free dom of movement that comes with using the camera without a tripod . The flexibility of different lighting heads and the abundance of power has in recent years encouraged photographers to return to simpler , daylight - quality style , using flash illumination bounced off white studio walls reflectors . YEH
استخدم هنري فوكس تالبوت الضوء المنبعث من شرارة لأول مرة لالتقاط صور تجريبية لأجسام قريبة في عام 1851. بينما كان المؤيد "الأفضل". كافحت الاستوديوهات الاحترافية مع الأضواء في ثمانينيات القرن التاسع عشر ، وكانت الاستوديوهات الأقل اهتمامًا ، ومعظم المصورين الهواة ، يستخدمون "إضاءة المغنيسيوم" التي سبقت فلاش التصوير الفوتوغرافي.
استخدم هنري فوكس تالبوت الضوء المنبعث من شرارة لأول مرة لالتقاط صور تجريبية لأجسام قريبة في عام 1851. بينما كان المؤيد "الأفضل". كافحت الاستوديوهات الاحترافية مع الأضواء في ثمانينيات القرن التاسع عشر ، وكانت الاستوديوهات الأقل اهتمامًا ، ومعظم المصورين الهواة ، يستخدمون "إضاءة المغنيسيوم" التي سبقت فلاش التصوير الفوتوغرافي.
Magnesium flash powder
Magnesium could be ignited in several ways : by blowing it into a candle flame ( above ) . pouring it through a funnel and applying a flame to it as it fell ( left ) . a or placing it on a tray and using a flint and wheel , triggered by a lever on the handle ( below ) , to make a spark . Flash duration was from 1 / 10-10 sec .
مسحوق فلاش المغنيسيوم يمكن إشعال المغنيسيوم بعدة طرق: عن طريق نفخه في لهب الشمعة (أعلاه). صبها من خلال قمع ووضع لهب عليه عند سقوطه (على اليسار). أ أو وضعها على صينية واستخدام صوان وعجلة ، يتم تشغيلهما بواسطة رافعة على المقبض (أدناه) ، لإحداث شرارة. كانت مدة الفلاش من 1 / 10-10 ثانية.